On the Rigidity of Ramanujan Graphs
نویسنده
چکیده
A graph G is generically [4] rigid in dimension one if and only if it contains a spanning tree, that is, a spanning subgraph assembled by inductively joining 1-simplices along 0-simplices. The analogous property is sufficient but not necessary for the generic rigidity of graphs in higher dimensions, that is, a generically rigid graph in R need not contain a spanning subgraph consisting of n-simplices joined along (n − 1)-simplices, see Figure 1a. Indeed, a graph which is generi-
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